When Hiroo Onoda got dropped off on in the Philippines during World War II, the Japanese soldier was told two things: 1) You are absolutely forbidden to die by your own hand. And 2) It may take three years, it may take five, but whatever happens, we'll come back for you. They didn't come back, but Onoda obeyed his orders—and kept fighting for 29 more years.

Onoda's guerrilla cell was one of the few that managed to stay live behind enemy lines. But when news of the war's end came, they still weren't ready to give up. Today I Found Out explains:

In October 1945, they came across a leaflet from the local islanders to them saying "The war ended August 15th. Come down from the mountains!" The few remaining cells discussed this leaflet extensively, but eventually decided that it was Allied propaganda trying to get them to give themselves up.

They felt that there was no way that Japan could have lost so quickly since the time when they were deployed. Indeed, this would seem strange to anyone who had no knowledge of the atomic bombs dropped on Hiroshima and Nagasaki. Also, another one of the cells had been fired upon just a few days before; they felt that this wouldn't have happened if the war was over.

Additional leaflets, newspapers—even photographs and letters from the soldiers' families—weren't enough to convince them. And after 29 years, Onoda was the only member of his cell left.

Finally, in 1974, a student hunting for Onoda found him, was unable to convince him that Japan had surrendered, and ultimately had to find Onoda's old commanding officer, who went to tell him the bad news in person.

On March 10th, 1975 at the age of 52, Onoda in full uniform that was somehow still immaculately kept, marched out of the jungle and surrendered his samurai sword to the Philippine President Ferdinand Marcos. Marcos, very unpopularly in the Philippines, but immensely popular in Japan, pardoned Onoda for his crimes, given that Onoda had thought he was still at war the entire time.